Hongxing Li1, Yi Luo1, Binglei Jiang1, Yinglong Lai2, Wensheng Yue1, Duo Huang1*1Department of Ultrasound Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China2Department of Cardiothoracic Surgery Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China*Corresponding author: Duo Huang, Department of Ultrasound Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China. E-mail: huangduo1986@163.com.